CHICAGO (CBS) — His testimony as a 12-year-old helped convict a Humboldt Park man of murder, but now an Ohio man says he had the wrong suspect.

As WBBM Newsradio’s Nancy Harty reports, Orlando Lopez says he told Chicago Police after he identified Jacques Rivera as the gunman in a 1988 murder that he saw the real killer a week later.

LISTEN: WBBM Newsradio’s Nancy Harty reports

Lopez says police didn’t believe him and thought he was afraid of gang retaliation, so he decided to stick with his original story.

So Rivera was convicted of the murder of Felix Valentin, who was shot 11 times in a car. He is now serving an 80-year sentence.

Police detectives visited Valentin in the hospital twice and he identified two different men as the shooter, including Rivera. But Valentin died 18 days after the shooting, leaving Lopez as the only witness.

More than two decades later now, an investigator for the Center for Wrongful Convictions at Northwestern University found Lopez as part of efforts to get a hearing for Rivera.

Cook County Judge Neera Walsh ruled Thursday that Lopez’s statements to his church pastor admitting the misidentification over 10 years ago were not admissible.

Also Thursday, prosecutors put former detective Gillian McLaughlin on the witness stand and she said she did not remember Lopez ever approaching authorities in 1988 and telling them that he had changed his mind about Rivera.

After the hearing, Rivera’s mother, Gwen Rivera, said she was cautiously optimistic that her son would walk away from prison.

“This could turn it around,” Rivera said. “Anything can happen.”

The attorneys on the case are scheduled to make their final arguments Aug. 24.

The Chicago Sun-Times contributed to this report, via the Sun-Times Media Wire.